When you get a bare lie around the green, either because the grass is really short or there's not much of it, there's a premium on hitting the ball first. The best way to do that is to play it farther back in your stance -- the worse the lie, the farther back the ball goes. To make sure you get it back there, try this: Place the clubhead behind the ball with your right hand only and step into your stance with your right foot first, lining up the ball with your instep (1). Then set your left foot -- taking a narrow stance -- and complete your grip.
Don't change anything else from your normal chipping technique. Your weight should favor your front foot, with the shaft leaning forward (2). From there, swing the club up going back and focus on hitting the ball first.
As for club selection, it's fine to chip with your lob wedge from these tight lies. Playing the ball back will turn it into a pitching wedge or 9-iron.
To be a good bunker player, you have to understand how the club is supposed to move through the sand. The bottom of a sand wedge is designed to bounce, not dig, when it contacts the sand. This is the whole deal in bunker play. Your goal is to hit a couple of inches behind the ball and let the clubhead skid under it.
Open the clubface slightly, play the ball forward and let the club bounce through the sand (right). Once you get a feel for this, you'll think bunker shots are easy. See video below.
Butch Harmon is a Golf Digest Teaching Professional and runs the Butch Harmon School of Golf, at Rio Secco, in Henderson, Nev.